xref: /freebsd/contrib/tcpdump/print-rt6.c (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 #define NETDISSECT_REWORKED
23 #ifdef HAVE_CONFIG_H
24 #include "config.h"
25 #endif
26 
27 #ifdef INET6
28 
29 #include <tcpdump-stdinc.h>
30 
31 #include <string.h>
32 
33 #include "ip6.h"
34 
35 #include "interface.h"
36 #include "addrtoname.h"
37 #include "extract.h"
38 
39 int
40 rt6_print(netdissect_options *ndo, register const u_char *bp, const u_char *bp2 _U_)
41 {
42 	register const struct ip6_rthdr *dp;
43 	register const struct ip6_rthdr0 *dp0;
44 	register const u_char *ep;
45 	int i, len;
46 	register const struct in6_addr *addr;
47 	const struct in6_addr *last_addr = NULL;
48 
49 	dp = (struct ip6_rthdr *)bp;
50 	len = dp->ip6r_len;
51 
52 	/* 'ep' points to the end of available data. */
53 	ep = ndo->ndo_snapend;
54 
55 	ND_TCHECK(dp->ip6r_segleft);
56 
57 	ND_PRINT((ndo, "srcrt (len=%d", dp->ip6r_len));	/*)*/
58 	ND_PRINT((ndo, ", type=%d", dp->ip6r_type));
59 	ND_PRINT((ndo, ", segleft=%d", dp->ip6r_segleft));
60 
61 	switch (dp->ip6r_type) {
62 #ifndef IPV6_RTHDR_TYPE_0
63 #define IPV6_RTHDR_TYPE_0 0
64 #endif
65 #ifndef IPV6_RTHDR_TYPE_2
66 #define IPV6_RTHDR_TYPE_2 2
67 #endif
68 	case IPV6_RTHDR_TYPE_0:
69 	case IPV6_RTHDR_TYPE_2:			/* Mobile IPv6 ID-20 */
70 		dp0 = (struct ip6_rthdr0 *)dp;
71 
72 		ND_TCHECK(dp0->ip6r0_reserved);
73 		if (dp0->ip6r0_reserved || ndo->ndo_vflag) {
74 			ND_PRINT((ndo, ", rsv=0x%0x",
75 			    EXTRACT_32BITS(&dp0->ip6r0_reserved)));
76 		}
77 
78 		if (len % 2 == 1)
79 			goto trunc;
80 		len >>= 1;
81 		addr = &dp0->ip6r0_addr[0];
82 		for (i = 0; i < len; i++) {
83 			if ((u_char *)(addr + 1) > ep)
84 				goto trunc;
85 
86 			ND_PRINT((ndo, ", [%d]%s", i, ip6addr_string(ndo, addr)));
87 			last_addr = addr;
88 			addr++;
89 		}
90 		/*
91 		 * the destination address used in the pseudo-header is that of the final
92 		 * destination : the last address of the routing header
93 		 */
94 		if (last_addr != NULL) {
95 			struct ip6_hdr *ip6 = (struct ip6_hdr *)bp2;
96 			UNALIGNED_MEMCPY(&ip6->ip6_dst, last_addr, sizeof (struct in6_addr));
97 		}
98 		/*(*/
99 		ND_PRINT((ndo, ") "));
100 		return((dp0->ip6r0_len + 1) << 3);
101 		break;
102 	default:
103 		goto trunc;
104 		break;
105 	}
106 
107  trunc:
108 	ND_PRINT((ndo, "[|srcrt]"));
109 	return -1;
110 }
111 #endif /* INET6 */
112